*{
    /* 写在body中是无效的,这是因为继承属性被块级元素原始属性content-box覆盖 */
    box-sizing: border-box;
}
body{
    margin: 0;
}
#product-overview{
    background-color: #ff1688;
    /* padding: 20px;
    border: 5px solid black;
    margin: 20px; */
    width: 100%;
    height: 528px;
}
#product-overview h1{
    color: #fff;
    margin: 0;
}
#product-plan h1{
    color: rgb(47, 188, 96)
}
.main-header{
    width: 100%;
    background-color: rgb(47, 188, 96);
    padding: 10px;
}
.main_nav__item{
    display: inline-block;
}
.main_nav{
    display: inline-block;
    text-align: right;  /* 设置行内块元素右对齐,因为行内块类似于文字 */
    width: calc(100% - 54px);        /* 设置宽度全部扩展 在减去main_logo的宽度49px再减去空格5px */
}
.main_nav__item{
    margin: 0;
    padding: 0;
    list-style: none;
}
.main_logo{
    display: inline-block;
}
.main_brand{
    
}